Cardiovascular risk factors in children from the Belgian province of Luxembourg. The Belgian Luxembourg Child Study

The Province of Luxembourg is an area in Belgium with a high prevalence of risk factors for cardiovascular disease and non-insulin-dependent diabetes mellitus among adults. In the present study, children in the age groups 6-8, 8-10, and 10-12 years were selected at random from school classes (n = 1,028), with a participation rate of 70.3%. Anthropometric factors, blood pressure, and fasting blood glucose, plasma cholesterol, triglyceride, and insulin levels were measured in 1992. All anthropometric and metabolic variables increased with age, except for waist: hip circumference ratio in boys and cholesterol in girls. In the oldest group, girls who had passed menarche were taller and heavier and had greater skinfold, body mass index, insulin, and systolic blood pressure values but lower total cholesterol levels and waist: hip ratios than girls who had not passed menarche. Boys had lower skinfolds and higher waist: hip ratios than girls in all age groups, and were significantly shorter and lighter in the oldest age group. There was no difference in body mass index between the two sexes. Girls had higher triglyceride and insulin levels in the 10- to 12-year age group, lower blood glucose values in the 8-10 and 10-12 age groups, and lower diastolic blood pressures in the 8-10 age group. Obesity, blood glucose, triglycerides, insulin, and blood pressure were highly interrelated. Cholesterol, triglycerides, insulin, and blood pressure values were all among the highest of values previously reported in other studies. The deciles of body mass index above 50 appeared to be particularly elevated, suggesting that obesity, when present, was pronounced in this population of children. These findings suggest an accumulation of genetic susceptibility to cardiovascular disease and non-insulin-dependent diabetes mellitus in this stable, ethnically homogeneous, and rather isolated part of continental Europe.

Direct stimulatory effect of insulin-like growth factor-I on monocyte and macrophage tumor necrosis factor-alpha production

GH has been demonstrated to play a physiological role in the priming of macrophages for tumor necrosis factor-alpha (TNF alpha) synthesis. Although evidence has been presented that GH exerts this effect by an indirect mechanism, the mediators of GH stimulation of TNF alpha synthesis have not been identified. Because insulin-like growth factor-I (IGF-I) is a major mediator of many GH effects, in the present study we investigated the direct in vitro effect of this growth factor on macrophage TNF alpha production. Treatment of murine macrophages with physiological concentrations of IGF-I (0.13-130 nM) enhanced both basal and lipopolysaccharide-stimulated macrophage TNF alpha release and messenger RNA levels. Induction of basal TNF alpha production was also observed after treatment of the cells with supraphysiological concentrations of insulin (130-1300 nM). Exposure of human monocytes to IGF-I led to a similar increase of basal TNF alpha production and messenger RNA expression. Preexposure of macrophages with specific antibodies against IGF-I and IGF-I receptor before IGF-I addition resulted in a complete abrogation of the stimulatory effect of IGF-I on TNF alpha production, indicating that specific binding of IGF-I to its receptor is required for macrophage TNF alpha induction by IGF-I. In contrast to the stimulatory effect of IGF-I, neither GH (0.1-10 micrograms/ml) nor IGF-II (0.13-130 nM) enhanced macrophage TNF alpha release in vitro. To assess the role of the tyrosine kinase system in mediating IGF-I-induced basal TNF alpha production, macrophages were preincubated with the specific tyrosine kinase inhibitors, genistein and tyrphostin A9, before IGF-I exposure. Addition of these compounds resulted in a dose-dependent inhibition of the stimulatory effect of IGF-I on macrophage TNF alpha release, indicating that protein tyrosine kinase activation is required for TNF alpha stimulation by IGF-I. Taken together, these results demonstrate that IGF-I is a monocyte/macrophage activating factor that enhances TNF alpha production, and that such effect is mediated via the IGF-I receptor and involves tyrosine kinase activation.

Internal carbohydrate complexity of the oligosaccharide chains of recombinant human follicle stimulating hormone (Puregon, Org 32489): a comparison with Metrodin and Metrodin-HP

Glycoforms of recombinant human follicle stimulating hormone (rhFSH) (Org 32489, Puregon) were characterized using concanavalin A lectin affinity chromatography to reveal information about the internal carbohydrate complexity (extent of carbohydrate side-chain branching) of the preparations. The rhFSH glycoforms were measured by radioimmunoassay and a two-site immunoradiometric assay and compared with those in two urinary preparations (Metrodin and Metrodin-HP) used in assisted reproduction programmes and a urinary FSH international standard 70/45 (uFSH IS 70/45). Similar data were obtained with both assays; rhFSH had 6% complex internal carbohydrate structures compared with 22-27% for Metrodin, Metrodin-HP and uFSH. The proportion of simple carbohydrate structures was also different, with rhFSH having 18.5 compared with 4.5-9.3% for Metrodin, Metrodin-HP and uFSH. A linear relationship was observed between the percentage glycoforms with an isoelectric point (pl) < 4 and the log percentage simple forms (logarithmic regression; r = 0.93) indicating a direct relationship between carbohydrate complexity and charge heterogeneity. In summary, rhFSH contains fewer complex forms and an increased proportion of simple carbohydrate structures in comparison with Metrodin, Metrodin-HP and IS 70/45.

Recombinant human luteinizing hormone: a partial physicochemical, biological and immunological characterization

The aim of this study was to partially characterize the glycoform composition of a recombinant human luteinizing hormone preparation (rhLH; Serono), an early version of the material (LHadi) which is currently being assessed for clinical application. Specifically, the charge (pl) and internal carbohydrate complexity of this rhLH was examined and compared with that of an alternative commercially available form of recombinant LH (Crystal Chem) and a pituitary International Reference Preparation (IRP). All preparations were separated by charge by chromatofocusing them on a pH gradient (7-4) using a 4 ml mono-P column is conjunction with a fast performance liquid chromatography system and by complexity of the oligosaccharide structures using concanavalin A (con-A) lectin affinity chromatography. LH in both the unfractionated and fractionated material was assessed by immunoradiometric assay (IRMA, I-LH) and by the in-vitro Leydig cell bioassay (B-LH). Both assays were calibrated against IRP 80/552. The in-vitro biopotency of the preparations was 18187 (Serono rhLH), 12063 (Crystal Chem rhLH) and 6658 (80/552) IU/mg; biological:immunological ratios were 1.14 (80/552), 1.90 (Crystal Chem rhLH) and 1.99 (Serono rhLH). However, similar qualitative data were obtained by both bioassay and immunoradiometric assay following fractionation, with the median pl of the bioactive LH in the preparations being 5.5 (24% > pH 6), 5.52 (18% > pH 6) and 4.97 (0% > pH 6) for the Serono, Crystal Chem and pituitary preparations respectively. Further all three contain < 1% of the complex carbohydrate structures and between 36-44% and 56-63% of the intermediate and simple forms of bioactive LH. In conclusion, the Serono recombinant LH preparation has a higher in-vitro bioactivity and is more basic than the other two preparations although the complexity of its carbohydrate moities appears to be similar.

Pancreatic islet macroencapsulation: a new device for the evaluation of artificial membrane

We propose a new device especially designed to test membranes for islet macroencapsulation. It is composed of three independent parts: a support made of three polytetrafluoroethylene rings, the membrane that forms the walls of the encapsulation chamber, and a collagen gel that immobilizes the islets. Studies of this device were performed with the AN69 membrane. After 2 months of implantation in the peritoneal cavity of rats, the empty device was found to be biocompatible, referred to as weak cellular adhesion. In vitro the encapsulation preserved the peak of insulin release in response to high glucose during a perifusion test (0.36 +/- 0.02 microU/ml/islet for free or encapsulated islets). As a result of the collagen gel, the morphological aspect and functional activity were still preserved after 7 days of culture. In vivo xenotransplantation into diabetic mice normalized the fasting glycemia up to 30 days. Numerous macrophages adhered to the outer surface of the membrane, and a layer of cells emerging from the destruction of islets covered the inner surface. In addition, the morphological aspect of many islets was altered. By showing that the AN69 membrane was only partially efficient for islet xenotransplantation, this new device proved to be of interest for testing a variety of membranes.

A search for immunoglobulins inhibiting gonadal cell steroidogenesis in premature ovarian failure

Premature ovarian failure (POF) may be caused by the action of circulating gonadotrophin receptor-blocking antibodies. Luteinizing hormone (LH)-stimulated testosterone production from mouse Leydig cells and follicle stimulating hormone (FSH)-stimulated oestradiol production from immature rat Sertoli cells were therefore studied in the presence of protein-G purified immunoglobulin G (IgG) samples from control subjects (n = 9), infertile women with elevated early follicular phase FSH levels but otherwise normal menstrual cycles (n = 10), and patients with POF (n = 10) or Graves' disease (n = 10). A saturating and subsaturating (78% for LH; 60% for FSH) dose of each hormone was chosen for study. A commercial preparation of human IgG (Sigma IgG, 0.75 mg/ml) employed as negative control had no effect on basal or gonadotrophin-stimulated steroidogenesis. In its presence, saturating doses of LH (2 IU/l) and FSH (20 IU/l) gave rise to 11.2 +/- 0.8 (n = 7) and 25.1 +/- 5.8 (n = 8) fold increases in steroid secretion. IgG (0.75 mg/ml) had no effect in the four groups on LH-stimulated testosterone outputs using a saturating (2 IU/l) or subsaturating (1 IU/l) dose of hormone. For example, LH (2 IU/l)-stimulated testosterone production was 94% (83-96 median; interquartile range) and 88% (81-99) of the Sigma IgG control for control and POF groups respectively. However, four out of nine IgG samples from the normal subjects (mean +/- SEM = 86 +/- 6%), two out of 10 of the high FSH group (77 +/- 4%), five out of 10 with Graves' disease (86 +/- 3%) and six out of 10 with POF (76 +/- 6%) gave rise to LH (2 IU/l)-stimulated testosterone outputs which were lower (P < 0.05) than that of Sigma IgG control. Using the identical set of patients and an IgG concentration of 0.25 mg/ml, the FSH-stimulated oestradiol outputs of the four groups were similar when using either the saturating (20 IU/l) or subsaturating (5 IU/l) dose of the hormone. Thus, the percentage of FSH (20 IU/l)-stimulated oestradiol production of the Sigma IgG control was 81 (66-89 median, interquartile range) and 50 (38-84) for control and POF groups respectively. However, once again individual patients had inhibitory IgGs such that four out of nine (controls), three out of 10 (high FSH group), four out of 10 (Graves' disease) and six out of 10 (POF patients) inhibited (P < 0.05) FSH (20 IU/l)-stimulated oestradiol secretion by 52 +/- 9 (mean +/- SEM), 44 +/- 7, 52 +/- 6 and 41 +/- 6% respectively. Of the patients with inhibitory IgGs the extent of inhibition of gonadotrophin-stimulated steroid secretion was similar between the groups. In conclusion, there is little evidence to suggest that immunoglobulins blocking gonadotrophin receptors are a mechanism for POF in a large proportion of women suffering from this condition.

Can the wound healing process be improved by vitamin supplementation? Experimental study on humans

The improvement of the wound healing process in humans by vitamin supplements is still controversial because of the lack of a clearly demonstrated correlation with the mechanical properties of scars.

OBJECTIVE

The aim of this work was to study the effects of high doses of ascorbic acid (AA) and pantothenic acid (PA) on the wound healing process of human skin.

METHOD

Two groups of patients undergoing surgery for tattoo removal by the successive resection procedure received AA (1 or 3 g/day) and PA (0.2 or 0.9 g/day). More than 80 mechanical, biological and histological parameters were investigated in both preoperated skin and the scars.

RESULTS

The breaking energy of scars was higher in group 2, and energy and treatment were directly correlated (p = 0.006). Mg and Mn significantly rose in group 2 whereas Fe decreased in a dose-dependent manner. Intragroup comparison showed patient and treatment effects for Mg, a time.treatment effect for Cu and a treatment effect for Fe.

CONCLUSION

The degree and rapidity of variations rather than the variations of the absolute values themselves of fibroblasts, hydroxyproline, Fe, Cu and Mg are significantly related to the enhancement of the mechanical properties of scars. From this study, it may be assumed that in order to obtain 'better', more solid and resistant scars, the decrease of Fe must be quick and acute in order to avoid the harmful effects of toxic radicals; the increase of Cu, Mg and Mn must be early and high in order to have more stable and solid collagen.

The effect of eccentric exercise on serum creatine kinase activity in different ethnic groups

Eccentric exercise causes release of muscle creatine kinase (CK) 3-4 days after exercise. Racial variation in basal serum CK has been reported but the reasons for this are unknown. We studied 30 subjects of different ethnic origin (Caucasian, Afro-Caribbean, Asian) before and after eccentric exercise. Basal serum CK was significantly higher in the Afro-Caribbean group (201 +/- 134 IU/L, median +/- SD) compared to Caucasians (81 +/- 57 IU/L). The Asian group had intermediate CK values (144 +/- 93 IU/L). The intra-individual range of peak post-exercise CK values obtained was very wide (95-30 200 IU/L) with little difference in median CK between the Afro-Caribbean (8450 +/- 9020 IU/L) and Caucasian groups (7600 +/- 8800 IU/L). The median value for the Asian group was lower (594 +/- 5410 IU/L). A sub-group of 15 individuals undertook a second bout of exercise 2 weeks later and all subjects demonstrated a training effect resulting in a marked attenuation of enzyme efflux. The variation in CK between the ethnic groups was not related to measurements of muscle strength or body mass, although the torque: body mass ratio followed the same order as the basal CK, i.e. the Afro-Caribbeans had the highest values. These results highlight the importance of considering ethnic origin and previous exercise history when interpreting serum CK assay results.

Role of oxidant injury on macrophage lipoprotein lipase (LPL) production and sensitivity to LPL

We investigated, in the present study, the role of reactive oxygen intermediates (ROI) in the control of macrophage lipoprotein lipase (LPL) secretion. Exposure of murine macrophages to increasing concentrations of hydrogen peroxide (H2O2) resulted in enhanced basal LPL production and mRNA levels. The increase of LPL production was reduced in the presence of antioxidants. Oxidant stress also modulated the regulation of macrophage LPL production by tumor necrosis factor alpha (TNF alpha). While antioxidants accentuated the inhibition of LPL by TNF alpha, addition of H2O2 significantly attenuated TNF alpha-induced LPL inhibition. As LPL has been shown to induce macrophage TNF alpha release, the effect of reactive oxygen species on LPL-induced TNF alpha production was also examined. Simultaneous treatment of macrophages with LPL and H2O2 or pretreatment of macrophages with H2O2 prior to LPL stimulation decreased the LPL-induced TNF alpha release by macrophages to the same extent. Under these experimental conditions, LPL binding to macrophages was markedly decreased. These data indicate that ROI are effective enhancers of macrophage LPL production and modulate macrophage response to LPL. These effects may represent additional mechanisms through which oxidant stress may participate to the development of atherosclerosis.

Small bowel biopsy by remote control: experimental study on dogs

Telemetry has been used for 30 years in medicine because it requires no link between patients and apparatus. To take advantage of this, we have developed a multipurpose intestinal capsule for the small bowel, with interchangeable tips triggered by remote control. A new tip, performing small bowel mucosal biopsy by remote control is presented. The location of the capsule is radiotransmitted by means of a cogwheel, which is rotated by contact with the intestinal wall. At the chosen site (ie, a number of centimeters from the pylorus), the remote control is activated and the mucosal biopsy is performed through a suction port and kept inside the tip. The capsule then passes throughout the bowel and is recovered in the stool to allow examination of the biopsies. The results of 24 studies on a dog (crossing of the pylorus, length, transit time, velocity) are analyzed to validate the method. Biopsies were accomplished in the stomach, the small bowel (ileum), and the colon. The device failed two times, but no complications occurred. Biopsies, with average surfaces were 6mm2, never penetrated the longitudinal muscular layer. The system is precise to within 3 cm, efficient, reliable, noninvasive, and causes minimal discomfort during investigation.

Tumor vascularity--a novel prognostic factor in advanced cervical carcinoma

OBJECTIVE

In the search for the optimal treatment of advanced cervical cancer, the identification of valid prognostic factors obtainable without histopathologic investigation of the entire tumor and the locoregional lymph nodes is of paramount interest. Tumor microvessel density has recently been demonstrated to correlate strongly with disease aggressiveness in breast cancer and other malignancies.

METHODS

We established a computerized image analysis system to quantify tumor microvascularity by using the closest-individual method, which determines the distribution of distances from random points within the tumor to the closest microvessel (DTCMV). Tumor microvascularity was assessed in paraffin sections of two cylindrical 2 x 20-mm core biopsies obtained transvaginally from the 12 and 6 o'clock positions of each tumor and then immunohistochemically stained for Factor VIII-related antigen. The oncologic relevance of tumor vascularity is studied in an open prospective trial.

RESULTS

Tumor vascularity was quantified in 42 patients with cervical cancers > 3 cm in largest diameter, FIGO stages Ib-IVa. This new parameter representing pathophysiological tumor-host interactions was independent of various other patient and tumor characteristics, including age, FIGO stage, tumor size, differentiation, lymph node metastases and lymphatic space involvement. Thirty-nine patients were treated with curative intent either by primary surgery (n = 22) or radiation (n = 17). After a median observation time of 18 months (range 4-41 months), the patients with higher tumor vascularity (mean DTCMV < 83 microns) had significantly shorter disease-free (P = 0.025) and overall (P = 0.032) survival probabilities than patients with lower tumor vascularity (mean DTCMV > or = 83 microns). Cox regression analysis identified tumor vascularity as the strongest independent prognostic factor in this group of patients.

CONCLUSIONS

The assessment of tumor microvascularity by computerized image analysis of defined tumor biopsies could become a novel means of predicting tumor aggressiveness in non-early cervical cancer.

Influence of Microphallus hoffmanni (Trematoda, Microphallidae) on the survival, sexual selection, and fecundity of Gammarus aequicauda (Amphipoda)

We investigated the influence of Microphallus hoffmanni (Trematoda) on the survival, mating success, and fecundity of its intermediate host, Gammarus aequicauda (Amphipoda). Despite the great size of M. hoffmanni metacercariae, the mean parasite abundance and the ratio of the variance to the mean abundance increased with host size, suggesting that accumulation of this parasite had no significant effect on the survival of its host. Size-assortative pairing was significant and we found no evidence of a parasite-mediated reduction in male competitiveness. Fecundity was reduced in infected females. Our results are in contrast to those obtained with helminths that alter the intermediate host's behaviour to favour their transmission to the definitive host.

Familial trends of obesity through three generations: the Belgian-Luxembourg child study

Province de Luxembourg in Belgium is an area with clustering of obesity as well as other risk factors for cardiovascular diseases and non-insulin dependent diabetes mellitus. In this study, obesity was studied in a total of 1028 boys and girls in age-strata 6-8, 8-10, 10-12 years, selected at random from school classes. Participation rate was about 70%. Non-participants did not differ from participants in comparisons of school records of height and weight. Furthermore, information on birth weight, parents' height and weight was collected, as well as reported problems of obesity in grandparents. The results show a high prevalence of pronounced obesity in these children. BMIs were strongly correlated between the children and both parents. Furthermore, grandparents' obesity problems were related to the BMI of parents, and also to obesity indices in the children. Birth weights were related to current BMI of the children (in girls only for the youngest age-group), and to their mothers' BMI. It was concluded that obesity is prevalent in this area and can be traced through three generations, and seems to be discoverable already at birth. Energy intake is high and physical activity level is low in these children. However, statistical analyses suggest that familial factors exert a greater impact than environmental factors on the BMI of the children. These results, as well as the wide-spread, consistent familial clustering of obesity, traceable already at birth, suggest influence of strong genetic traits for obesity in this population.

Variability in the immunoreactive and bioactive follicle stimulating hormone content of human urinary menopausal gonadotrophin preparations

The within- and between-batch variation in the immunoreactive and in-vitro bioactive FSH content of Pergonal, Metrodin and Metrodin-HP was investigated. Three batches of Pergonal and Metrodin, consisting of three ampoules in each batch, and three batches of Metrodin-HP, consisting of between one and three ampoules per batch, were selected at random. The follicle stimulating hormone (FSH) content of Pergonal, Metrodin and Metrodin-HP was determined by radioimmunoassay (R-FSH) and the in-vitro rat Sertoli cell bioassay (B-FSH) using the international urinary standard 70/45. The variability in the FSH content of the preparations was evaluated within and between batches by analysis of variance. Within-batch variability of B-FSH was not observed in Pergonal or Metrodin-HP but was seen in two batches of Metrodin in which the potency varied by up to 2.4 fold (P = 0.03). The between-batch R-FSH potencies of Pergonal (P1-P3) varied, with P2 (59.8 +/- 0.6) and P3 (61.7 +/- 0.9) being higher than P1 (47.1 +/- 1.5 mean +/- SEM IU/ampoule, P < 0.01). A similar pattern of variability was observed for B-FSH. For Metrodin, each of the batch R-FSH potencies was dissimilar (P < 0.02), with estimates ranging from 34.9 +/- 1.2 to 64.3 +/- 1.8 IU/ampoule. Furthermore, the extensive within-batch B-FSH variation from two batches confounded any meaningful comparison of between-batch variability. For Metrodin-HP, there was no between-batch B-FSH variation (29.0 +/- 6.1 to 33.0 +/- 0.3 IU/ampoule) and the R-FSH content was also well controlled (41.2 +/- 0.5 to 46.9 +/- 1.1 IU/ampoule).(ABSTRACT TRUNCATED AT 250 WORDS)

In-vitro biopotency and glycoform distribution of recombinant human follicle stimulating hormone (Org 32489), Metrodin and Metrodin-HP

In this study the in-vitro biopotency and glycoform distribution of human recombinant follicle stimulating hormone (FSH, Org 32489) has been assessed. The biopotency of recombinant FSH was studied using animal (rat Sertoli) and human (granulosa-lutein) cell models. Recombinant FSH, as measured in the rat Sertoli cell assay, was more potent than the urinary preparations Metrodin, Metrodin-HP and IS 70/45 with half maximal stimulation (ED50; mean +/- SEM, n > 3) occurring at 2.2 +/- 0.5 IU/I (recombinant FSH), 4.7 +/- 1.1 IU/I (Metrodin), 13.2 +/- 0.7 IU/I (Metrodin-HP) and 6.4 +/- 0.3 IU/I (IS 70/45); the pituitary preparation IRP 83/575 had an ED50 of 10.4 +/- 0.1 IU/I. Using human granulosa-lutein cells, cultured for up to 4 days in the absence of exogenous steroid precursors, recombinant FSH was either without effect (three out of five patients) or inhibited both oestradiol and progesterone secretion. FSH (83/575) was without effect on oestradiol with preparations from any of the patients but slightly stimulated (134 +/- 8%; mean +/- SEM, P < 0.05) progesterone production at the highest dose (80 IU/I). The distribution of FSH isoforms, assessed by polyclonal radioimmunoassay, following chromatofocusing over the ranges pH < 3.5 and pH 3.5-7.0 respectively was recombinant FSH, 12.4 and 87.6%; Metrodin, 19.8 and 80.2%; Metrodin-HP, 50.2 and 49.8%; IS 70/45, 15.0 and 85.0%; IS 83/575, 70.9 and 29.1%. All glycoforms were pI < 7.0 for the five preparations.(ABSTRACT TRUNCATED AT 250 WORDS)

Lipoprotein lipase synergizes with interferon gamma to induce macrophage nitric oxide synthetase mRNA expression and nitric oxide production

Lipoprotein lipase (LPL) induces macrophage tumor necrosis factor-alpha (TNF-alpha) gene expression and protein secretion. Since TNF-alpha can increase interferon gamma (IFN-gamma)-dependent nitric oxide (NO) production, we studied whether LPL may synergize with IFN-gamma for the induction of macrophage NO production. Although ineffective by itself, LPL in combination with IFN-gamma increased L-arginine-dependent NO production in a dose-dependent manner. Preincubation of LPL with an anti-LPL neutralizing antibody totally suppressed this effect. Increased NO synthetase (NOS) mRNA expression was also observed after macrophage treatment with IFN-gamma and LPL. Protein synthesis was required for the induction of NOS mRNA, and a TNF-alpha-mediated effect of LPL on NOS gene expression and NO production was observed. The ability of LPL to augment IFN-gamma-dependent NOS mRNA expression was associated with an increase in the NOS gene transcriptional activity but not in the NOS mRNA stability. Finally, binding of nuclear proteins to the nuclear factor-kappa B- and TNF-alpha-responsive sequences of the macrophage NOS promotor was decreased by treatment of the cells by IFN-gamma alone or in combination with LPL. These data provide evidence for a link between LPL and arginine metabolism in macrophages and further stress the role of LPL in the regulation of macrophage activation.

[The intestinal capsule: a new way of investigating the small intestine]

The small bowel is difficult to explore because of its location far away from the natural orifices. The aim of this study is to describe a telemetric, autonomous and multifunctional capsule (39 mm in length and 11 mm in diameter) designed according to a modular system to explore the small bowel. It consists of a central cylinder containing a location detector which allows permanent data collection concerning its position in the small bowel, the length of the small bowel and the transit velocity; secondly, several interchangeable tips allow either aspiration of a sample of intestinal juice, or release of a substance previously placed in the capsule, or to perform a mucosal biopsy. After having been swallowed by the patient, the capsule passes through the whole gut and is then recovered in the stools between 24 and 48 hours later. The preliminary study consisted of comparing, in patients undergoing a surgical procedure, the small bowel length measured by telemetry (542.3 +/- 113.8 cm) to that measured intraoperatively by the arithmetical mean of the mesenteric and antimesenteric edges (515 +/- 112.7 cm), p = 0.28. These different interchangeable working tips have already been used to determine the level of absorption of various substances, the discovery of absorption sites and the performance of mucosal biopsies without any material link between patient and the measuring or recording equipment. The main advantages of this intestinal capsule are the possibility to continuously transmit its location, its total autonomy and remote control of the desired action.

Effect of pantothenic acid and ascorbic acid supplementation on human skin wound healing process. A double-blind, prospective and randomized trial

This study aimed at testing human skin wound healing improvement by a 21-day supplementation of 1.0 g ascorbic acid (AA) and 0.2 g pantothenic acid (PA). 49 patients undergoing surgery for tattoos, by the successive resections procedure, entered a double-blind, prospective and randomized study. Tests performed on both skin and scars determined: hydroxyproline concentrations, number of fibroblasts, trace element contents and mechanical properties. In the 18 supplemented patients, it was shown that in skin (day 8) Fe increased (p < 0.05) and Mn decreased (p < 0.05); in scars (day 21), Cu (p = 0.07) and Mn (p < 0.01) decreased, and Mg (p < 0.05) increased; the mechanical properties of scars in group A were significantly correlated to their contents in Fe, Cu and Zn, whereas no correlation was shown in group B. In blood, AA increased after surgery with supplementation, whereas it decreased in controls. Although no major improvement of the would healing process could be documented in this study, our results suggest that the benefit of AA and PA supplementation could be due to the variations of the trace elements, as they are correlated to mechanical properties of the scars.

Structure of the bovine follicle-stimulating hormone receptor complementary DNA and expression in bovine tissues

We report the complementary DNA structure obtained by reverse transcription and polymerase chain reaction amplification encoding the complete amino acid sequence for the bovine follicle-stimulating hormone receptor (bFSHr). The deduced amino acid sequence for the cDNA revealed a mature polypeptide consisting of 678 amino acids (theoretical weight of 76.4 kDa) and a 17 amino acid putative leading signal peptide. The receptor consists of a large NH2-terminal extracellular membrane domain of 349 aa with 3 potential N-linked glycosylation sites, a transmembrane domain (264 aa) consisting of 7 putative membrane spanning segments, and an intracytoplasmic COOH-terminal domain (65 aa). Four potential phosphorylation sites were found in the transmembrane domain and the COOH-terminal domain. The amino acid sequence is 97%, 89%, and 88% homologous to the ovine, human, and rat FSHr respectively, with complete conservation of the 22 cysteine residues in the whole protein and the 3 N-linked glycosylation sites on the extracellular membrane domain. Northern blot analysis of total mRNA in bovine tissues revealed a major mRNA transcript of 2.55 kb for the bFSHr in the ovary without corpus luteum, and in the testis. No expression was found in other tissues analyzed. Total RNA from bovine granulosa cells collected from pregnant mare serum gonadotropin (PMSG)-treated prepubertal heifers showed 2 major mRNA transcripts of 6.8 and 2.55 kb, and 3 minor transcripts of 3.8, 3.3, and 1.6 kb. Bovine granulosa cells cultured with porcine FSH (0, 2, 10 ng/ml) for 4 days showed a decrease in the steady state level of the FSHr mRNA.(ABSTRACT TRUNCATED AT 250 WORDS)

[Subcapsular liver hematoma, a HELLP syndrome complication]

The authors report a case of unruptured subcapsular haematoma of the liver in a 31-year-old woman, para 2, in the 34th week of pregnancy, complicated by preeclampsia. Clinical signs of preeclampsia were associated with pain in the right hypocondrium and laboratory findings consistent with a true HELLP syndrome. The diagnosis of subcapsular haematoma was confirmed by tomodensimetry. A cesarean section was carried out but a conservative treatment of the hepatic haematoma was decided. Regular X-ray follow-ups showed the regression of the hepatic lesion. This case confirms recent reports that patients with unruptured capsular haematoma should be treated conservatively but should receive careful monitoring.

Exogenous steroids and the control of oestradiol secretion by human granulosa-lutein cells by follicle stimulating hormone and insulin-like growth factor-I

This study first examined the relative activities of 17 alpha-hydroxylase, 17,20-lyase and aromatase in human granulosa-lutein cells by challenging the cells with steroid precursors in the oestradiol biosynthetic pathway. When cells from four patients were challenged with precursor steroids on the pathway to oestrogen synthesis (pregnenolone, 17 alpha-hydroxypregnenolone, progesterone, 17 alpha-hydroxyprogesterone and androstenedione at 5 x 10(-6) M), oestradiol (nmol/l) outputs after 1 day of culture were (median, interquartile range) as follows: 4.1 (2.1-8.8; pregnenolone), 3.1 (1.7-6.0; progesterone), 12.5 (6.9-18.1; 17 alpha-hydroxypregnenolone), 8.2 (4.1-16.7; 17 alpha-hydroxyprogesterone) and 251 (140-819; androstenedione). No further increases were seen when the steroid concentration was increased to 1 x 10(-5) M. Basal oestradiol secretion was 3.5 (1.6-8.2) nmol/l. We conclude that the conversion of pregnenolone/progesterone to oestradiol by granulosa-lutein cells is rate limited by 17 alpha-hydroxylase activity but that these cells are capable of oestradiol secretion (in the nmol/l range) in the absence of androstenedione. In the second part of this study we examined the control of granulosa-lutein oestradiol secretion by follicle stimulating hormone (FSH) and insulin-like growth factor-I (IGF-I) in the presence and absence of exogenous androstenedione (10(-6) M). Cells were cultured for up to 6 days and basal oestradiol (nmol/l) fell dramatically over this period both in the presence and absence of androtenedione, e.g. from 339 (223-419) (median and interquartile range, cells from five patients cultured in the presence of androstenedion) after 2 days to 14 (7-59) after 6 days.(ABSTRACT TRUNCATED AT 250 WORDS)

[Diffuse neonatal hemangiomatosis. A case with tetralogy of Fallot]

In neonatal disseminated hemangiomatosis, multiple immature capillary hemangiomas are widely distributed in the skin, mucous membranes, and internal organs including the liver, lungs, and larynx. In patients with life-threatening visceral involvement, corticosteroids or interferon may be required. A case in a female infant with tetralogy of Fallot is reported.

Insulin-like growth factor-I stimulated growth and progesterone production by granulosa-lutein cells. Lack of interaction with physiological concentrations of luteinizing hormone and follicle stimulating hormone

This study examined the effect of physiological concentrations of insulin-like growth factor-I (IGF-I), follicle stimulating hormone (FSH) and luteinizing hormone (LH) alone and in combination on growth and progesterone production by human granulosa-lutein cells. Granulosa-lutein cells were obtained from patients (n > 5) undergoing in-vitro fertilization (IVF) or gamete intra-Fallopian transfer (GIFT) treatment. Cells were cultured for 2 and 4 days in the presence of physiological concentrations of human LH (code 68/40, 5 IU/l), FSH (code 83/575, 20 IU/l), or IGF-I (30 ng/ml) alone and in combination. Medium was changed every 2 days. No change in cell number (relative to each patient's own control) was observed after treatment with FSH or LH alone or in combination at any time. IGF-I alone produced a 117 +/- 8% and 176 +/- 15% (mean +/- SEM, n = 5) increase in cell number after 2 and 4 days respectively. This increase was unaffected by the addition of LH or FSH at any time. Basal progesterone secretion was variable (1633, 975-2409 nmol/l, median and interquartile range, day 2) and decreased with time in culture (564, 375-1089 nmol/l, day 4). After 2 days culture progesterone output increased by 116 +/- 5% of control in response to LH and 153 +/- 13% (mean +/- SEM, n = 5) of control in response to IGF-I. After 4 days, LH and IGF-I stimulated progesterone levels by 279 +/- 52% and 264 +/- 37% (mean +/- SEM, n = 5) respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

A left visual field bias for semantic encoding of unattended words

Previous studies have shown that verbal processing in both normal individuals and a split-brain patient can be strongly affected by the semantic category of an unattended word presented to the left visual field (LVF). The effect was interpreted in terms of inhibition, since responses were slower when the unattended LVF word belonged to the same category as the target word. The present experiment discriminated between two alternative explanations for this finding. Subjects were presented with two letter strings, one in central vision and one to the left or right of centre. Subjects made a speeded lexical decision to the central string, and were instructed to ignore the lateral string. When a word was presented to the LVF subjects responded more slowly when it was semantically related to the central word. When an unattended word was presented to the RVF, its semantic relationship to the central word had no effect on decision latency. This finding is discussed in relation to views of performance laterality and selective attention.

Microheterogeneity of thyroid-stimulating hormone from the pituitaries of euthyroid, hypothyroid and hyperthyroid rats

The microheterogeneity of pituitary thyroid-stimulating hormone (TSH) is dependent on variations in the hormone's carbohydrate moieties. In this study, changes in the pattern of heterogeneity have been assessed by chromatofocusing, which separates the isospecies on the basis of their isoelectric points (pI). Rats (n = 6 per group) were either untreated or rendered hypo- or hyperthyroid by including in the drinking water either propylthiouracil (0.05% for 8 weeks) or thyroxine (T4; 4 mg/l for 6 weeks) before they were killed at 16 weeks. On autopsy, serum TSH and total T4 were (means +/- S.E.M.): 2 +/- 0.3 micrograms TSH/l and 64 +/- 5 nmol T4/l (control); < 1 microgram TSH/l and 133 +/- 6 nmol T4/l (hyperthyroid); 58 +/- 6 micrograms TSH/l and 32 +/- 6 nmol T4/l (hypothyroid). The pituitaries were individually homogenized and the TSH isoforms separated by chromatofocusing over a pH range of 7-4. Fractions were assayed for TSH by radioimmunoassay. TSH from the control group was distributed into seven major peaks with pI values of (means +/- S.E.M., n = 6) 6.9 +/- 0.1, 6.6 +/- 0.1, 6.2 +/- 0.1, 5.8 +/- 0.1, 5.5 +/- 0.1, 5.2 +/- 0.1 and 4.8 +/- 0.1; 7 +/- 3% of the TSH had a pI of < 4.0. Six peaks of TSH were conserved in the hypothyroid group (with pI values of 6.8 +/- 0.1, 6.5 +/- 0.1, 6.2 +/- 0.1, 5.8 +/- 0.1, 5.4 +/- 0.1 and 5.2 +/- 0.1), and 11 +/- 4% of the hormone had a pI of < 4.0.(ABSTRACT TRUNCATED AT 250 WORDS)

Different isoforms of human pituitary thyroid-stimulating hormone have different relative biological activities

The relationship between the immunological and biological activities of thyroid-stimulating hormone (TSH) isoforms present in the three human pituitary preparations 68/38 (1st IRP), 80/558 (2nd IRP) and 63/14 (MRC Research Standard A) was investigated. The isoforms were separated by chromatofocusing. Six peaks of immunoactivity were detected in 80/558, with pI values (means +/- S.E.M.) of 6.6 +/- 0.1, 6.2 +/- 0.1, 5.9 +/- 0.1, 5.5 +/- 0.1, 5.2 +/- 0.1 and 4.9 +/- 0.1. Four peaks, with pI values of 6.8 +/- 0.1, 5.9 +/- 0.1, 5.5 +/- 0.1 and 5.2 +/- 0.1, were observed for 68/38. Standard 63/14 had five peaks, with pI values of 6.9 +/- 0.1, 6.4 +/- 0.1, 5.9 +/- 0.1, 5.4 +/- 0.1 and 4.9 +/- 0.1. For each standard, six fractions around the peak areas and at the top and bottom of the gradient were pooled and microconcentrated to < 1.0 ml. Microconcentrated TSH samples were assayed in three TSH bioassays based upon FRTL-5 thyroid cells, utilizing cyclic AMP accumulation, iodide and thymidine uptake as end-points and standard 80/558 as reference preparation. The more acidic forms of TSH showed a higher biological:immunological (B:I) ratio for cyclic AMP accumulation with, for example, 63/14 having a maximum of 3.7 (pI 4.9) and a minimum of < 0.7 (pI 6.9). In contrast, the maximum and minimum B:I ratios for iodide uptake for 63/14 were 3.8 (pI 6.9) and < 0.8 (pI 4.6), and for thymidine uptake, maximum and minimum ratios were 7.2 (pI 6.9) and 1.1 (pI 4.6) respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Human chorionic gonadotrophin contributes to the bioactivity of Pergonal

OBJECTIVE

We examined batch variation in the LH-like bioactive content of Pergonal and determined whether hCG contributes to this.

DESIGN

Random selection of three batches of Pergonal, consisting of three ampoules in each batch.

MEASUREMENTS

The LH content in each ampoule was determined by radioimmunoassay (R-LH), immunoradiometric assay (I-LH) and in vitro Leydig cell bioassay (B-LH) using the urinary hMG International Standard 70/45. Human chorionic gonadotrophin was determined by immunoradiometric assay (I-hCG) using the hCG IRP 75/537. The isohormone content of each batch was examined by chromatofocussing over the range pH 4.5-7.0 and the fractions collected were assayed for LH and hCG content. The variability in potency between batches was assessed by single factor analysis of variance.

RESULTS

The gonadotrophin content of each batch (IU/ampoule, mean +/- SEM, n = 3 ampoules) was R-LH (40.9 +/- 0.5, 40.8 +/- 0.2, 39.3 +/- 0.7, P > 0.15), I-LH (39.0 +/- 1.5, 28.3 +/- 0.8, 36.9 +/- 3.3, P < 0.001), B-LH (27.3 +/- 0.3, 12.0 +/- 0.9, 19.3 +/- 0.9, P < 0.001) and I-hCG (16.4 +/- 0.7, 11.7 +/- 0.2, 10.5 +/- 0.5, P < 0.001). The chromatofocussing recoveries below pH 5.5 expressed as a percentage of the total amount of analyte eluted from the column and collated for all three batches of Pergonal were (mean % +/- SD, n = 3 batches) R-LH (58.4 +/- 4.0), I-LH (41.3 +/- 7.5), B-LH (81.4 +/- 2.8) and I-hCG (87.8 +/- 3.7).

CONCLUSIONS

There was significant batch variation in the I-LH, B-LH and I-hCG (P < 0.001) but not the R-LH (P > 0.15) content of Pergonal. More than 80% of the total B-LH recovery chromatofocussed below pH 5.5 and corresponded to the region of highest I-hCG (> 87%) and lowest I-LH (< 42%) recovery. This was highly suggestive of hCG contributing to the LH-like bioactivity of Pergonal.

Variations of magnesium, iron, copper and zinc during the colonic wound healing process: experimental study on rabbits

The role of trace elements in the wound-healing process is still controversial. Their variations within a normal colonic wound healing have never been studied. An experimental study on rabbits was designed to study magnesium, iron, copper and zinc variations in blood, normal colonic walls and colonic anastomoses on each of the first 7 postoperative days. No major variations of Mg could be observed. Fe decreased in blood as well as in colonic walls and anastomoses. Cu increased in blood, whereas it decreased in colonic walls and anastomoses. Zn decreased in blood, whereas it increased in colonic walls without significant changes in anastomoses. The role of Fe seemed to be rather difficult to understand. Plasma mobilization seems to explain the local use of Zn, while early tissue release with further return in blood occurred for Cu. The importance of a well-balanced nutritional status is underlined to prevent and correct the variations of trace elements in the postoperative course.

Determination by latex immunoassay of protein 1 in normal and pathological urine

A sensitive latex particle assay has been developed to study the occurrence of protein 1 in human urine. The coefficients of variation (CVs) of the method which is fully automated vary between 3 and 11.5%. The assayable concentration range is 0.3 to 40 micrograms/l. Protein 1 is clearly a sex-dependent protein. In contrast to urinary retinol-binding protein (RBP) which shows no variation with age or sex, protein 1 is excreted in greater amounts in males from the puberty. In adults, the mean concentration of protein 1 in urine of men is approximately 5 times that of women. In the urine from both sexes, protein 1 occurs as a single component with a Mr around 21,000 and an pI of about 4.8. Protein 1 is correlated with RBP in the urine from female or male patients with impaired proximal tubular function, which suggests that it is handled by the kidney in a similar manner as RBP. Diabetics, however, show elevations of urinary protein 1 which do not correlate with the RBP excretion but with the albuminuria. A competition between albumin and protein 1 for renal tubular uptake might explain this paradoxical behaviour of protein 1 in the course of diabetic nephropathy.

Follicle-stimulating hormone-dependent estrogen secretion by rat Sertoli cells in vitro: modulation by calcium

We have investigated the role of Ca2+ in the control of FSH-induced estradiol secretion by Sertoli cells isolated from 8-10 days old rats. Exogenous Ca2+ (4-8 mmol/l) inhibited FSH-stimulated E2 secretion such that, with 8 mmol/l Ca2+ and FSH (8 IU/l) E2 secretion decreased from 2091 +/- 322 to 1480 +/- 84 pmol/l (p less than 0.002), whilst chelation of Ca2+ in the culture medium with EGTA (3 mmol/l) increased E2 secretion from 360 +/- 45 to 1242 +/- 133 pmol/l) in the absence of FSH. Further, EGTA (3 mmol/l) markedly potentiated FSH (8 IU/l), forskolin (1 mumol/l) and dibutyryl cAMP (1 mmol/l)-stimulated E2 secretion. Addition of the Ca2+ ionophores, ionomycin (2-5 mumol/l) and A23187 (2 mumol/l), inhibited FSH (8 IU/l)-stimulated E2 secretion by greater than 80%. The effect of ionomycin was totally reversible, whereas that of A23187 was irreversible. Ionomycin (5 mumol/l) had no effect on EGTA-induced E2 secretion in the absence of FSH, but reduced EGTA-provoked E2 secretion by 59% in the presence of FSH (8 IU/l). Similarly, forskolin- and dibutyryl cAMP-provoked E2 production was inhibited 46-50% by ionomycin (5 mumol/l). We conclude that FSH-induced E2 secretion from immature rat Sertoli cells is modulated by intra- and extracellular Ca2+.

Inhibition of protein kinase C by staurosporine increases estrogen secretion by rat Sertoli cells

We have examined the effect of inhibition of protein kinase C activity by staurosporine on estradiol secretion by Sertoli cells isolated from 8-10 days old rats. Staurosporine lead to a dose-related increase in estradiol secretion independent of FSH, such that with 100 nmol/l staurosporine basal estradiol levels increased 10-fold. The maximal response seen with staurosporine alone (100 nmol/l) or in combination with FSH (0.4-8 IU/l) was similar to that seen with a saturating dose of FSH (8 IU/l). There was no evidence of synergy between FSH and staurosporine. Activation of protein kinase C by phorbol 12,13 dibutyrate (10(-7) mol/l) resulted in a 53-74% inhibition of estradiol production provoked by FSH (8 IU/l), staurosporine (5-100 nmol/l) or staurosporine in combination with FSH. Staurosporine (5-100 nmol/l), in the absence or presence of FSH, was unable to overcome inhibition of estradiol secretion by phorbol ester, indicating the presence of at least two independent binding sites on protein kinase C for these molecules. Forskolin (1 mumol/l)- and dibutyryl cAMP (1 mmol/l)-stimulated estradiol secretion was inhibited by 31 +/- 5% and 64 +/- 5% respectively, by phorbol 12,13 dibutyrate (10(-7) mol/l). We conclude that FSH-induced estradiol secretion in immature rat Sertoli cells is affected by protein kinase C activity.

Peripheral visual changes and spatial attention

Three experiments are reported investigating the attentional effects of peripheral visual changes. In agreement with previous work, experiment 1 demonstrated facilitatory and inhibitory effects of a peripheral visual change on the latency of peripheral target detection. However, after a few minutes practice the facilitatory effect disappeared entirely. The inhibitory effect, though slightly reduced in later blocks, remained significant. Hence, the two effects are dissociable and not inter-dependent as argued by Maylor (1985). In experiments 2 and 3 the perceptual salience of the peripheral cue was manipulated. With a low energy, barely noticeable cue there was no reduction in either facilitation or inhibition as a function of practice. In contrast, the attentional effects of cues higher in energy tended to diminish with practice. Theoretical implications of these data are discussed.

Autonomous telemetric capsule to explore the small bowel

An intestinal telemetric capsule has been developed to study the small bowel in man. It consists of a cylinder (11 mm in diameter and 39 mm in length) containing a location detector, a radiotransmitter, a lithium battery and an interchangeable tip. After having been swallowed by the patient, the capsule passes through the whole gut and is recovered in the stools. During the transit through the small bowel, the information provided by the radiotransmitter allows continuous monitoring of the distance covered from the pylorus, the direction and the velocity of progression. Moreover, according to the type of interchangeable tip, it is possible, by remote control, to sample 0.5 ml of intraluminal fluid for subsequent analysis or to release 1 ml of any liquid substance in a precisely determined place for pharmacological studies. The main originality of the capsule is its ability to transmit its precise location inside the small bowel.

Urinary proteins and red blood cell membrane negative charges in diabetes mellitus

The nature and origin of proteinuria in diabetes mellitus have been investigated by measuring the urinary excretion of seven specific proteins of low (beta 2-microglobin, retinol-binding protein) or high molecular weight (albumin, transferrin, hemopexin and IgG). Using the Alcian Blue binding test, we also measured negative charges on red blood cell (RBC) membrane which according to recent studies might mirror the glomerular polyanion charge. A group of 190 diabetics was examined, including 90 patients with type I diabetes, 23 type II diabetics treated with diet and/or hypoglycaemic agents and 77 longstanding type II diabetics requiring insulin therapy. With the exception of beta 2-microglobulin all proteins measured were excreted in the urine of diabetics in significantly higher amounts than in controls. The assay of transferrin proved the most sensitive (58% positive) followed by albumin (49%), IgG (34%), hemopexin (28%) and retinol-binding protein (26%). Practically the same ranking was obtained when only type I diabetics were considered. RBC membrane negative charges were diminished in diabetics and negatively correlated with the urinary excretion of albumin (r = -0.61, n = 190). RBC charges were also negatively correlated with other urinary proteins of high molecular mass (r between - 0.5 and - 0.2) but presented no relation with urinary beta 2-microglobulin or retinol-binding protein. The loss of RBC charges in diabetics most likely reflects the concomitant depletion of the glomerular polyanion responsible for the increased glomerular leakage of high molecular mass plasma proteins. The preferential increase in transferrin excretion together with the progressive rise in the urinary excretion of IgG lead us to postulate that the loss of glomerular polyanion in diabetes is accompanied, from the early stage, by a progressive decrease in the size-selectivity of the glomerular filter. The urinary excretion of retinol-binding protein was weakly correlated with albuminuria (r = 0.26, n = 186). Eight % of diabetics showed an elevation of urinary retinol-binding protein without evidence of microalbuminuria, which clearly demonstrates that a proximal tubular impairment can occur independently of the glomerular alterations in the course of diabetic nephropathy.

ACTH adrenal cell bioassay: improved sensitivity (12 ng/L) achieved by immunoextraction of ACTH from human plasma by a monoclonal antibody

We have previously reported a bioassay for human plasma ACTH based upon trypsin dispersed guinea-pig adrenal cells which was sensitive to 100 ng/L ACTH in unextracted human plasma when measured against human pituitary ACTH (1-39) standard 74/555. We now present a bioassay of increased sensitivity (12 ng/L) which incorporates three major changes. The trypsin/trypsin inhibitor step in the cell dispersion protocol has been replaced with collagenase, donor calf serum (3%) has been incorporated into the standard curve and ACTH has been extracted from human plasma and dilutions of standard hormone by a sephacryl bound monoclonal antibody (2A3) directed towards the 25-39 sequence. The extracted standard curve has a detection limit of 6 ng/L and the cells can tolerate up to 50% plasma equivalent concentration. Thus, the improved assay has a detection limit of 12 ng/L ACTH in plasma. The assay can now measure bioactive plasma ACTH levels reliably in the normal range.

The effect of some antiprostatic steroids upon cortisol production by guinea-pig adrenal cells stimulated by ACTH

The antiprostatic steroids 6-methylene-4-pregnene-3,20-dione (6-MP) (I), 17-alpha-acetoxy-6, 16-dimethylene-4-pregnene-3,20-dione (II), and melengestrol acetate (MGA) (III) were incubated with guinea-pig adrenal cells, both alone and maximally stimulated with ACTH. Cortisol output was then measured by RIA. Increased cortisol-like secretion was obtained with 6-MP in the absence of ACTH. In the presence of ACTH, cortisol-like steroid secretion was the sum of that seen with ACTH and 6-MP alone. It follows that 6-MP stimulates in vitro a cortisol-like steroid cross reacting with the cortisol antibody by a mechanism that by-passes ACTH. Steroid (II) weakly inhibited cortisol output. MGA, in contrast, proved to be a strong inhibitor of cortisol output (ID50 of 2.3 mumol/l). Its site of action was established by adding it to adrenal cells incubated with precursor steroids on the cortisol pathway. Conversion of 3 beta-hydroxysteroids to cortisol was inhibited whereas conversion of 3-keto steroids was not affected. It follows that MGA inhibits 3 beta-hydroxysteroid dehydrogenase.

Gastric bezoar: another side effect of endoscopic variceal sclerotherapy

Gastric bezoars were observed after esophageal variceal injection of polidocanol in 5 of 56 patients with alcoholic cirrhosis treated by endoscopic sclerosis. We suggest that endoscopic sclerotherapy could have induced a transient vagal injury resulting in delayed gastric emptying and subsequent bezoar formation. Although the volume of sclerosant (25-35 ml per session) and the length of the injector needle (4 mm) were the same in all patients, two reasons could explain the occurrence of bezoars in these five patients: a deeper injection of sclerosant, and a worsening of a preexistent vagal neuropathy due to diabetes mellitus and/or alcoholism.

Assessment of the bioactivity of human and bovine thyrotrophin preparations using a porcine thyroid cell bioassay

The biopotency of six preparations of thyrotrophin (TSH) has been compared in a highly sensitive in vitro porcine thyroid cell bioassay using iodide uptake as an endpoint. Three of these preparations were of human origin and three derived from bovine pituitary tissue. One human TSH preparation, the 2nd International Reference Preparation, 80/558, was used to calibrate the other five. The log dose-log response curves for all preparations were sigmoidal in shape. For the purpose of evaluation the central linear portions of the curves were compared. With all preparations the slopes in this region were very similar. The relative biopotencies of the bovine preparations (unit:unit) were at least five times those of the human standards when measured using the porcine thyroid cell bioassay. These findings emphasise the need to control the TSH standards employed in a variety of bioassays, particularly those used for between-laboratory comparison.